The present invention relates to collecting information about traffic along roads in a geographic area, and in particular, the present invention relates to an efficient way for collecting real-time traffic information.
Traffic information is used for various purposes. Commuters use traffic information to plan their commutes to work. Trucking companies use traffic information to plan routes that minimize delays. Delivery companies use traffic information to determine routes that are most efficient. Government agencies use traffic information for emergency response purposes, as well as to plan new highways and make other improvements.
There are different kinds of traffic information. Real-time traffic information indicates the actual conditions that exist on roadways at the present time. Historical traffic information indicates the long-term average traffic conditions that have existed on roadways over a period of time. There are also different types of traffic information that are collected. For example, one important type of traffic information relates to traffic incidents (e.g., accidents) that have relatively short-term but significant effects. Other important types of traffic information include traffic flow, traffic volume, transit times, throughput and average speed.
There are various ways to collect traffic information. One way to collect traffic information is to place sensors along roadways. Another way to collect traffic information is to observe traffic conditions from a tall building or aircraft (e.g., a traffic helicopter). Still another way to obtain traffic information is to have a number of vehicles travel along roads and report traffic information back to a traffic information center.
Although these existing ways to collect traffic information are satisfactory, there still exists room for improvements. Infrastructure-based methods are associated with relatively high deployment costs thereby limiting them to major roads. Vehicle-based methods are associated with communications and processing costs that have limited deployment of these methods as well. Accordingly, it would be beneficial to have a method that collects traffic information for a large number of roads efficiently and reliably.
To address these and other objectives, the present invention includes a system and method for collecting traffic information. One or more aircraft, such as helicopters, fly predetermined flight paths above a geographic area. These aircraft may be piloted or remotely controlled. The flight paths are determined so that portions of roads for which traffic information are to be collected are within the ranges of remote velocity sensors located on board the aircraft during the flights of these aircraft along their respective flight paths. Each aircraft includes positioning equipment that allows the precise position (i.e., altitude, latitude, and longitude) and attitude (i.e., roll, pitch, and yaw) of the aircraft during its flight to be determined. During a flight along the predetermined flight path, the remote velocity sensor in each aircraft is operated to perform scans of locations on roadways in the geographic area. Taking into account the location, velocity and attitude of the aircraft while each scan is being made, data indicating traffic conditions from the scanned output are matched to a precise road map database and the traffic flows on every scanned road are thereby collected.